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Date:   Mon, 3 Jan 2022 23:43:39 -0800
From:   Christoph Hellwig <hch@infradead.org>
To:     Randy Dunlap <rdunlap@infradead.org>
Cc:     linux-kernel@vger.kernel.org, Jason Gunthorpe <jgg@nvidia.com>,
        Jeff Dike <jdike@addtoit.com>,
        Richard Weinberger <richard@nod.at>,
        Anton Ivanov <anton.ivanov@cambridgegreys.com>,
        Johannes Berg <johannes@sipsolutions.net>,
        linux-rdma@vger.kernel.org, linux-um@lists.infradead.org
Subject: Re: [PATCH 2/2] IB/rdmavt: modify rdmavt/qp.c for UML
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Yikes, this rdmavt code is completely fucked up and a very good example
why people should not use __user casts or random internal helpers.

The right fix is to remove this crap entirely, and if the rdmavt
maintainer think that they absolutely need a non-temporal memcpy they
need to work to add a core API for it.